Machine for reducing printing plates to uniform thickness



Dec. 16, 1929. w. QCLAYBOYURN r 5 MACHINE FOR REDUCING PRINTING PLATES TO UNIFORM THICKNESS Filed May 14. 1928 a She ets-Sheet 1 Dec. 10, 1,929. 1.. w. CLAYBOURN 1,738,759

MACHINE FOR REDUCING PRINTING PLATES TO UNIFORM THICKNESS Filed May 14, 1928 8 Sheets-Sheet 2 fig; 4.

. /NVENTOR.'

Dec. 10, 1929. L. w. CLAYBOURN 1,733,759

MACHINE FOR REDUCING PRINTING PLATES TO UNIFORM THICKNESS Filed May 14, 1928 8 Sheets-Sheet 3 Dec. 10, 1929. w, CLAYBOLIRN 1,738,759

MACHINE FOR REDUCING PRINTING PLATES TO UNIFORM THICKNESS lNl/EN TOR.-

1929- a L. w. CLAYBOURN 3 ,759

MACHINE FOR REDUCING PRINTING PLATES TO UNIFORM THICKNESS Dec. 10, 1929.

L. W. CLAYBOURN MACHINE FOR REDUCING PRINTING PLATES TO UNIFORM THICKNESS Filed May 14, 1928 8 Sheets-Sheet Dec. 10, 1929. 1.. w. CLAYBOURN 1,738,759

MACHINE FOR REDUCING PRINTING PLAT ES TO UNIRQRM THICKNESS Filed May 14, 1928 v 8 Sheets-Sheet 7 ms :1 244 243 um W I 234 245 I33 O 0 o O 342 zss //9 168111 l6? m 127 Dec. 10, 1929. L. w. CLAYBOURN MACHINE FOR REDUCING PRINTING PLATES TO UNIFORM THICKNESS Filed May 14. 1928 8 Sheets-Sheet A23 INVENTO Patented Dec. 10, 1929 OFFICE;

LESLIE W. CLAYBOURN, OF MILWAUKEE, WISCONSIN MACHINE non. nnnncine PRINTING PLATES TO, UNIFORM 'rnicxnnss I Application filed May 14,

My invention relates to machines for reducing printing plates to uniform thickness. The term printing plate as herein employed includes so-called electrotypes, etchings,

stereotypes, and the like, whether fiat or curved, and Whether less than type-high, or type-high or including bases.

' My present invention is an improvement on the invention shown, described and claimed in my applications for Letters Patent of the United States on improvements in shaving machines, respectively filed September 21, 1926, as Serial No. 136,841, and September 23, 1926, as Serial No. 137,265.

It is the object of my invention to provide a novel arrangement of rotary cutter-heads acting in different paths upon the back of the printing plate for reducing the printing plate I to proximate uniform thickness; further, to provide a novel arrangement of rotary cutter-' heads respectively divided into cutter-sections which act successivelyon the back of the printing plate, and preferably in overlapping relatiolnfor reducing the back of the printing plate to proximate uniform thickness; further, to provide a novel arrangement of rotary cutter-heads cutting in different paths and shaving means acting successively on the back of the'printing plate; further, to provide a plurality of rotary cutting agencies acting successively in overlapping relation on the back of the printing plate and shaving means so arranged that the plu rality of rotary cutting agenciesreduce the printing plate to proximate thickness followed by the action of the shaving means to reduce the printing plate to finished uniform thickness during a single relative travel between the rotary cutting agencies and the shaving means on the one part and the printing plate on the other part; further, to provide a rotary cutter-head having a plurality of cutter-sections including reversely slant-ing cutting edges in a machine of the. character mentioned whereby to reduce the end shifting strain between the rotary cutter-head and the printing plate; further, to provide a plu rality of such rotary cutter-heads .arranged to act simultaneously on the printing plate, the cutting portions of which overlap each 1928. Serial 1T0. 277,570.

provide a novel arrangement of cutter-heads,

shaving means and presser means for the printing plate; further to provide a rotary cutter-head having sectional cutting portions 00 and presser means for the printing plate arranged to act on the printing plate between such sectional cutting portions; further, to

' supplement 'such rotary cutter-head and presser means with shaving means at the side of the rotary cutter-head andpresser means between the shaving means and the rotary cutter-head; further, to provide a plurality 'of rotary cutter-heads respectively provided with spaced-apart cutting portions and presser means for the printing plate located in the spaces between such cutting portions; and, further, to supplement such arrangement with shaving means, and presser means between the shaving means and the rotary cutter-heads. 7

It is the object of my invention further to provide novel means for mounting the cutterheads; further, to provide novel means for mounting the-presser means; further, to provide novel means for moving the presser means into' and out of active relation; further, to provide novel means for exposing the rotary cutter-heads; and, further, to provide. novel means for causing travel between the printing plate and the cutting agencies.

In the present exemplification of my in: Vention the printing plate .is caused to travel relative to the cutting agencies. It is ob-. vious that incertainphases of my invention traveling movement may be imparted to the cutting agencies while the printing plate is stationarily' positioned, within the purport of my invention and the scope of the appended :1 claims.

The invention will be further readily understood from the following description and claims, and from the drawings, in which latter: I

Fig. l'is a front elevation of my improved of Fig. 2.

device, and showing the carriage in assumed position in dotted lines.

Fig. 2 is an end elevation of the same. Fig. 3 is'a cross-sectional detail view, taken in the plane of the irregular line 33 of Fig. 4 is a plan view of my improved de vice, partly broken away.

Fig. 5 is a. rear view of the same. Fig. 6 is a vertical longitudinal section of the same, taken in the plane of the line 66 Fig. 7 is a side elevation showin the ad usting means for the shaving kni e, partly roken away.

Fig. 8 is a horizontal sectional bottom view detail of my improved device, taken in the plane of the line 8-8 of Fig; 6, partly broken away. V

'Fig. 9 is a vertical cross-sectional view of the same, taken in the lane of the'irre ular line 9 -9 of Fig. 6, part y broken away, s owin the presser means in lowered position.

I 1 10 is a similar view of the same, showing t e presser means in ra sed posltlon, and one of the end supportmg means for the rotary cutter-head released preparatory to removal of the r'otary cutter-head.

Fig. 11 is a cross-sctional view, taken in the plane of the line 11-11of Fig. 9, partly roken away.

Fig. 12 is an enlarged sectional detailview of one of-the presser means, taken in the plane of the line 1212 of Fig. 8.

Fig. 13 is a sectional detail view ofthe handle end of the operating arm, taken on the line 1313 of Fig. 1. I

Fig. 14 is a cross-section of my improved device, takenin the plane of the line 1414 of Fig. 10, partly broken away, showing the presser devices in raised position.

Fig. 15 is a cross-sectional detail View of the mounting for the presser-roller, taken in the plane of the line 1515 of Fig. 14.

Fig. 16 is a detail view of the presser devices and shaving deflectors, partly broken awayand viewed in the direction of the line 1,2, 6 and'9.)

1 616 of Fig. 14; and,

Fig. 17 is a bottom view of the printing plate showing the action of the cutting devices thereon. I

In the present exemplification, the frame 21 of the machine comprises a base 22. A carriage 23 is arranged tolreci rocate in the frame, the frame being provi ed with guideways 24 for guiding the carriage, the carriage having complemental guideways 25. (Figs.

Suitable means are provided for causing reciprocation of the carriage. I have shown a fluid under pressure, for instance oil received under pressure into a cylinder 27 on the frame; (Fig. 6),

' for actuating a piston 28 in the cylinder, the

' piston being on a piston-rod 29. The carriage is provided with a bracket 30, to which the piston-rod is secured by a reduced threaded end 31 of'the piston being received in a bearing 32 on the bracket and a nut 33 threaded over said threaded reduced end for clamping the bracket and consequently the carriage to the piston-rod.

Suitable fluid pressure creatin and control means for the oil are provi ed. Thus a casing 35, (Figs; 2, 5 and 6), is fixed to the frame and contains a suitable oil reservoir and a suitable pump for der pressure, the oil un er pressure being conducted from the pump through pipes 36, 37, communicating at their respective ends with the casing by means of ports 38, 39, and

. with the respective ends of the cylinder 27 through ports 40 and 41, these plpes being alternately employed as pressure pipes and as return pipes for return of the oil to the reservoir, depending on the direction m WhlCl'l 42, (Figs. 1, 2 and 5), the valves having corn v :nection with a valve operating rod 43 ar ranged to reciprocate in the valve-casing and to be operated by an arm 44, having articula tion therewith by means of a pin 45, the arm 44 being fixed to a shaft 46 journaled in bear-; ings 47, 48, in the base, andhaving an operating arm 49 fixed thereto.

An adjusting lever 51, (Figs. 2 and 5), controls a valve in the casing for adjustingthe rate of feed of the oil under pressurev for controlling the'speed of travel of the carriage. The adjustin plate 53 provided with registry marks for indicating the rate of feed. The adjusting lever is arranged to be clamped in place by a clamp-nut 54. Y The pump for. creating the pressure on the oil may be a usual gear-pump in the easing 35 driven by a shaft 58 journaled in the casing 5 and provided with a sprocket-pin- 'ion 59. actuated by an electric motor 60 supported in the base, the rotor of which has connection with a shaft 61 journaled, in the base and having a sprocket-pinion 62 fixed thereto. A suitable drive chain 63, which may be a so-called silent chain, is received about lever is provided. with a pointer 52 comp emental to a gagelacing the oil un- (Figs. 2, 5 and 6.) The pump is t the sprocket-pinions59, 62, for driving the pump.

The operatingl'ever 49 is provided with an operating handle 67 for controlling the --movements of the carriage, (Figs. 1, 2 and 13), the operating lever being arranged to be held in adjusted positions, as by means of a pull-pin 68 coacting with holes 69,70, 71 and 72 in a control-plate 73 fixed to the base, the shelf 74 of which may be provided with suitable indications for indicating deslred positions 91 the operating handle. The

' of the handle I carriage.

' the dotted position of the carriage shown in Fig. .1. If a quick traversing movement shifted toward the ri pull-pin is on a stem 75 fixed to the hub 76 this hub being movable endwise in a bearing 77 on the operating lever. The operating lever is provided with a socket 78 in which a flange 79 on the pull-pin is received. A spring 80 in the socket between said flange and the bottom'of the socket normally urges the pull-pin into the holes.

In the present exemplification, when the operating lever is in vertical positiona'nd the pull-pin 68 is in-the hole 71, the valves controlling the flow of fluid under pressure are in closed relation for rest position of the When the operating lever is shifted for locating the pull-pin in. the hole 7 0 the carriage is caused to travel in cutting direction at the rate of speed determined bythe adjustment of the feed control lever 51, this position ofthe. operating lever controlling the feeding movement of the carriage in cutting direction. This feeding movement is a movement of the carriage from the position shown in Fig. 6' toward the left, to

of the carriage in the same direction is desired, the control-lever is shifted farther in the same direction for causing registry of the pull-pin 68 with the hole 69.

If movement of the carriage in the opposite direction isdesired, the operating lever is ght, as viewed in Fig. 1, a quick traversing movement of the car riage being caused when the pull-pin 68 registers with the hole 72. This traversing movement of the carriage is a return of the carriage to its normal position shown in Fig. 6, for reception of the printing plate prior to the reducing operation. This return of the carriage is usually accomplished with a quick traversing movement. 7

The rate of speed of movement of the car riage is determined by the extent of the shifting of the operating lever 'out of its normal position. The movement of the carriage in either direction will cease upon limit of movementpf the piston 28 in the cylinder 27 being reached in either direction, the pump being provided with usual pressure relief means for relieving excess pressure in the cylinder, and suitable by-pass valves may be arranged to be opened upon the limit of travel of the t, I carriage in either directlon being reached,

for bypassing the fluid under pressure back to the reservoir when the piston reaches either of its limits of movements. i

The adjustment between the carriage and the cutters for determining thickness of the finished printing plate is shown accomplished by adjustment of the support for'the printing plate. The printing plate, instanced at 85, is supported on a bed 86, which is ad 'justabl'e up and down toward and from the cutters, betweenend guides 87, 88; and side guides 89, 90, on the carriage. (Figs. 6 and 113 is located on the I throughout the area of the prin .9.)5 The bottom of the bed is providedwith ribs 91 having inclined guideways 92 at their lower edges, (Figs. 6, 9 and 11), the latter coacting with inclined guideways 93 on ribs 94 on a slide 95' guided in longitudinal guideways 96 in the carriage. This slide forms a wedge between the carriage and the bed. Longitudinal movement of the wedge raises or lowers the bed, according to the direction of longitudinal movement of the wedge.

- This longitudinal movement of the wedge is shown accomplished by providing. the wedge with a threaded bearing 97 in which a screw-rod 98 is threaded. The screw-rod is rotatable in a bearing 99 on the carriage, and

is heldendwise in said hearing, as by a gear 100 and a collar 101. respectively fixed to said screw-rod at the respective ends of said bear ing. pinion 102 meshes with the gear 100 and is operated by a handle 103 for rotating the screw-rod. (Figs. 2 and.) The handle while rotating the pinion. also rotates suitable disks intergeared between the handle and pinion and provided with peripheral indicationswhich successively appearat openings 104 in a casing 105, in which the intergeared disks are located, for indicating the resultant ofthe adjusting rotation of the handle.

The carriage may be provided with remov able plates 111, 112. (Figs. 4 and 6.) A stop carriage. An edge of the printing plate is arranged to be placed against this stop. 1

The cutting devices are exemplified as a rotary cutter-head 117, a rotary cutter-head 118 and a shaving knife 119. (Figs. 8 and 11.)

'The' rotary cutter-heads are respectively exemplified as comprising sp cutter-sections 121, 122,- separated endwise respectively by spaces 123', 124. The cuttersections of each cutter-rhead are coincident transversely of the machine with the spaces of the other cutter-head, and cutter-sections of the respective cutter-heads preferably overlap each other transversely of the machine, so thatthe combined rotary cutter-heads reduce the printing. plate to proximate thickness ting plate. The cutting edges of thesections of the cutter-head are preferably oblique, (Figs. 4 and 8), the different cutter sections on'the same rotary cutter-head being preferably slanted "at opposite angles so thafl the end thrusts of the cutter-head upon the printing plate due to the obliqueness of the cutting edges is'substantially equalized, part-of the cutter-sections producing an endthrust in the one direction'and part of the cutter-sections on the same. cutt'er-head producing an end aced-apart rotary thrust in the opposite direction. The oblique .rotati'vely held to the shaft by keys 133 received in said key-grooves. The cutter-sections are separated byspacing collars 134. A collar 135 is located between the shoulder 131 and the cutter-section adjacent thereto. A collar 136 is located between the inner raceways 137 of roller bearings 138 and the cuttersection adj aoent thereto. A nut 139 is received over the threaded end 140 of the shaft and clamps the cutter-sections and collars and said inner raceways between said shoulder 131 and said nut. Said roller bearing comprisesa cage 141 having an adjustable end 142.

The opposite end of the cutter-shaft 1s formed as a plug 145-, shown of frusto-conical form, received in a complementally formed socket 146 of a journal-piece 147, held purnalwise in bearings 148, 149, in the main frame and held'against endwise movement therein.

. threaded socket 151 in the plug. A washer 152 is located between the outer end of the journal-piece and thehead 153 of the bolt. Rotation of the bolt in one direction draws the plug into the socket of the journal-p ece for rigidly fixing the shaft and journal-p ece together, with their axesof rotation'coincident.

a motor,

Sprocket-wheels 154, 155, are fixed .tothe respective journal pieces. (Figs. 5 and 8.) A sprocket-chain 156, which may be a socalled silent chain, is received loopwlse about said sprocket-wheels and about a sprocketpinion 157 fixed to the shaft 61, at the 1ns1de of the sprocket-pinion 62, and rotated by the v for rotating the cutter-heads.

The cutter-heads are rotated at high speeds and are provided with a number of cutting edges arranged about their periphcries and said cutting edges are comparatively'short, with the result that short chips are formedin the operation of the rotary cutterheads, and means are provided for drawing these chips awayfrom the cutter-heads" and y from the printing plate being operated on,

as soon as formed, as will be hereinafter more fully explained.

- The bearings at the driven ends ofthe rotary cutter-heads are shown mounted in a standard .161 at one side of the machine.

cutter-heads and is instanced as carrying presser devices arranged to press upon the printing platebeing operated on, for forcing the various portions of'the printing plate toward the supporting face of the bed, in order that all parts of the printing surface 163 of the printing plate 85, (Fig. 6), whichis presented toward said supporting surface,

are level with said supporting surface while the cutters are actin on the back or rear cent to said pressed-down portions. 7.

. The printing surface 163 of the printing .plate may be uneven in places and for inplate which of even thickness throughout its printing-portions.

The presser devices are instanced as including series 1-65, 166, 167 and-168, of presser devices, the rollers, of said respective series being spaced apart. 7 The respective rollers of the series 165,166,

are coincident with the spaces 123 between the A bolt 159 has a threaded end received 1n a cutter-sections of the rotary cutter-head 117, and the rollers of the series of presser devices 167 are coincident with the spaces 124 between the cutter-sections of the cutter-head 118. The rollers of this latter series are. offset with relation to the rollers of the series 165, 166. i

The rollers of the series of presser devices 165, 166, (see Fig. 8) are shown located in the path of the cutter sections of the cutter-head 118 and the rollers of the series.of presser ,face of the printing pate at or closely adja- (Figs. 4, 6, 8, 9 and 11.)

devices 167 are shown located in the path of the cutter sections of the cutter-head 117. In other words, the rollers of the series 165, 166, are locatedin the plane perpendicular to the axes of the cutter-heads in which the cutter:

sections of the cutter-head 118 are.located, and the rollers of the series 167 are located in the plane perpendicular to the cutter-heads in which the cutter-sections of the cutter-head 117 are located. The rollers of the series of presser devices 168 are located in laterally spaced apart relations between the rotary cutter-heads and the shaving knife. v These rollers of the respective presser de-- vices are located closely adjacent to the cutting edges of the cutter-section (see Figs. 8 and 11) while cutting, and at the ends of said cutter-sections. They extend into the vertical planes parallel with the axes of the respective cutter-heads in which the sections of the respective cutter-heads are located'.-

The respective presser rollers are journaled in forks 171 (see Fig. 12). The fork is provided with a pin 172 for supporting the roller, the roller "rotating on the pin. The i upper end of the fork is movable in a socket 173 in the bracket 162. The fork is provided with a shoulder-piece 174 from which astem -17 5 extends. The outer end of the stem is reciprocable in an adjusting bolt 176, adjustable in the outer threaded portion of a bore 177 in the bracket. A spring 178 between the shoulder-piece 174 and the adjusting bolt,

-normally causes movement of the presserroller toward the printing plate. The bolt 176 adjusts the tension of the spring 178.

Themovement of the presser-roller toward the bed is limited by a lip 179 on the fork .171 arranged to coact with the lip 180 on a lip-piece 181 releasably secured to the bracket. (Figs. 11, 12 and 15.) The lip 180 has a flat face 182, which coacts with a correspondingly shaped wall 183 in the lip-piece for preventing turning of the fork, and compelling the presser roller to maintain its path parallel,

with the direction oftravel of the printing plate.

, Each of the rollers is provided-with simi-' 'lar mounting, limiting and adjusting means.

The lip-pieces for the forks of the rollers of .the respective series 165,166, 167 and 168 of presser-rollers are respectively shown at 185, 186, 187 and 181, all of these lip-pieces being functionally and structurally similar.

.The bracket 162 is provided with openings 191 for the cutter sections of the cutter-head 117, and with openings-192 for the cutter sections of the cutter-head 118. (Figs. 4, 6, 8,

10 and 14.) These respective openings are separated by ribs 193, 194, in which respectively the presser devices of the'respective series 165, 167, are located. The bracket and the ribs thereof are providedwith recesses 195, 196, in which the spacing collars on the respective cutter-shafts are located when the bracket is lowered into working position, the

portions of the ribs and brackets at the respective sides of said recesses being located at the respective sides of ,the cutter-shafts when the bracket is in lowered position.

These openings also provide passagewa s for the chips made by the rotary cutter-hea s,

the chips passing through said openings an through passages 197, 198, ina hood 199 received above the bracket, communicating with a passage 200 in-the standard, when said bracket is in lowered position. The hood is fixed to the bracket by a; bolt 201 so as to make an air-tight-joint therewith.- The passage 197 is complemental to the cutter-head 117, and

the-passage 198 is complemental to the cut-- ter-head 118, The passage 200 is arranged to communicate with a suction-piece 202 suitabl secured to the standard, and communicatmg with all of'the openings in the bracket for drawing the chips through said openings,

through the hood, through the passage 200 -'-and the suction-piece 202. suita -blesuc- 'tion device and suction pip ng communicate with said suction-pieceior forming the'necessary suctlon for causing travel and removal of the chips as soon as said chips are formed.

The bracket is adjustable toward and from the cutter-heads for exposing the cutter-heads for attention and for withdrawing the cutterheads from the machine.

providing the standard 161 with guideways 205, guideways 206 on a slide-plate 207 coacting therewith. This slide-plate forms part of the bracket. A screw-rod 208 is j ournaled and held endwise in a bearing 209 on the bracket, and is threaded into a threaded bearing 210 on the standard. The screw-rod is provided with an operating end 211 for 'receiving a suitable wrench .for readily turn' ing the screw-rod for raising and lowering the bracket.

The position of the presser devices may be collectively adjusted with relation to the bed (Figs. 3 and 4.) The adjustment of the bracket is obtained by and with relation to the rotary cutter-heads at that side thereof toward which the cut-' ting edges of the cutter sections move in per-' forming the cutting stroke, are respectively provided with deflectors 217, 218, respectively 15.) These deflectors and braces are suitably secured to the bracket. They are located 7 at the infeeding sides of the respective rollers of the series 165, 167 of rollers, leaving the rollers however free to exert pressure and to yield to pressure. They are preferably wider than the rotary cutter sections with which they respectively coact.

The deflectors 217 are fixed in position by means of screws 221 received through bars 222 and bent portions of said deflectors and threaded into the bracket. Thebraces 219 are held in place by screws 223 received throu h holes inthe braces and threaded into t e bracket.- Locatin pins 224 prevent he deflectors 218 turning of said braces. are held in place by screws 225 received through holes in said deflectors and held to the bracket. Locating pins 226 prevent shiftin of said deflectors. The braces 220 are he d in place by screws 227 received throu h holes in said braces and threaded into t e j bracket.- Locatng pins 228 in saidbraces and bracket prevent shifting of the braces;

The lower portions of the peripheries of the presser rollers normally extend below the plane of the bottoms of the cylindrical paths m which the cutting edges 0 tors move, so as to exert pressure upon the the rotary cut- 1001 backed by braces 219, 220. (Figs. 8, 14 and Y printing plate while the printing plate is passing under the cutters, the presser rollers eing also raised by said pressure, resisted by the springs 17 8, for raising the lips 17 9 (Fig. 12) away from the lips 180. The shaving knife 119 is provided with a shaving edge 229, (Fig. 11), which is .operatively positioned slightly lower or nearer the supporting surface of the printing plate than said plane in which the lowest portions of said respective cylindrical paths are located, so as to remove a slight shaving off of the back of the printing plate and provide the back of the printing plate with a smooth surface while the printing plate has all portions of its printing surface pressed against the supporting face on the bed, so that the finished printing plate is of equal thickness throughout its printing portions between its printing face and its rear face.

The shaving knife is shown slantingly mounted on a supporting face 233 of a yoke 234. (Figs. 4, 5, 6,7 and 11.) The respective ends of the yoke are fixed to the frame, one of the ends being locatedin a recess 235 in the standard 161 and theother end of said yoke being located on a standard 236 at the '..other side of the frame, the respective ends of the yokebeing fixed to said standards respectively by bolts-237, 238.

The shaving knife is adjustable 'tion with relation to the bed. This is accomplished in the present instance by providing the shaving knife with slots 241, (Figs. 7 and 11), through which screws 242 pass and have threaded connection with the oke for clamping the shaving knife in ad- .justed positions. A locating bar 243 is fixed to the yoke, being received in a groove 244 therein, and clamped to the yoke by screws 245. It extends across the yoke above and.

spaced from the-knife. Adjusting bolts 247 are threaded in threaded bearings 248 in the bar and bear against the upper edge of the shaving knife foradjusting the shaving knife toward the'bed. 'Adjusting bolts 249 are threaded in threaded bearings 250 in the shaving knife ,for adjusting the shaving knife away from the bed. Rotation of the bolts 247; 249, adjusts the, shaving knife toward or from the plane of the bed, the

ard. guide-rib 259.,"rec'eived' in guide grooves 111 said bearin -block and said standard respectively, ai in positioning the to eleva-N bearing-block. When the bracket 162 is lowered position, its free end is fixed to the bearing-block for rigidly holding the parts Figs. 10 and 14 show the bracket and the pressure part-s mounted thereon in raised relation, and Fig. 10 shows the bearing-block in outwardly shifted relation to illustrate ease with which the parts may be dissociated for attention to the cutters and removal of the rotary cutter-heads. k

In operation, the printing plate is placed on the bed while the carriage is in retracted position. (See Fig. 6.) The carriage is moved in cutting direction so that the printing plate passes the cutters, the rotating cutter-heads reducing the printing plate to proximate thickness in separated narrow paths, the paths ofthe cutter-sections of the res ctive cutter-heads overlapping each o er,

the shaving knife thereupon acting-upon those portions of the printing plate so reduced to proximate thickness, for removing a slight shaving and reducing the printing plate to accurate even thickness throughout its printing portions, the printing plate passing all of the cutting devices at one operation for being reduced to uniform thickness and provided with a smooth ba'cln'ng' surface throughout, the carriage brought to rest after the cutting operation. :(See dot, ted lines in Fig. 1.) The printing plate is then removed from the bed, and the carriage is returned to normal position.

When the printing plate passes the cutter-head, the 'back of the printing-plate is provided with separated cut paths 264,.

ig. 17), produced by the spaced-apart cutter sections of the cutter-head 117, these paths reducing the printing plate along said paths to proximate uniform thickness. The

advancing movement of the printing plate next brings it into coaction with the cutter- 119, which removes a slight shaving from the back of the printing plate along the path 267 for reducing the printing plate to uniform exact thickness than hout its rinting portions and providing e back 0 the printing 113 head 118, the spaced-apart cutter-sections of l tained.

plate with an extremely even polished surace.

In my improved device the rough cutting is done by the rotary cutter-heads, and the 5 final cutting is done by the shaving knife, at

one feeding passage between the printing plate and thecutting devices. The duty of the shaving knife being slight a printing plate of extreme accuracy in thickness is ob- Having thus fully described my invention,

what I claim as new, and desire to secure by Letters Patent, is:

1. In a machine of the character described,

the combination of a plurality of rotary cutpresser means for each of said cutter-heads operating between cutter-sections of said cutter-head and opposite the cutter-sections of the other cutter-head.

2. In a machine of the character described,

the combination of a plurality of rotary out ter-heads comprising spaced-apart cuttersections, the cutter-sections of one cutterhead operating opposite the spaces between cutter-sections of another cutter-head, presser means for each of said cutter-heads operating between cutter-sections of said cutterbetween the-c tter-sections of said respective cutter-hea s, and means for elevating said presser means in the spaces between cut ter-sections above said cutter-sections.

6. In a machine of the character described, the combination of a bed, a plurality of cutting agencies arranged to cut the back of the printing plate, presser means in advance of said respective cutting agencies, and means for elevating said presser means past said cutting agencies.

7. In a machine of the character described,

the combination of a bed, a rotary cutter,

pressermeans, means for elevating said presser means above said rotary cutter, and means for endwise release of said rotary cutter between said bed and said presser means.

8. In a machine of the character described, the combination of a bed, a plurality of rotary cutter-heads respectively comprising spaced-apart cutter-sections respectively arranged to cut the back of the printing plate along separated paths, presser means acting between'the cutter-sections of said respective cutter-heads, means for elevating said presser means in, the spaces between cutter-sections above said cutter-sections, and means for endwise release of said rotary cutter heads between said bed and said presser means.

-9. -In a machine of the character described,

head and opposite the cutter-sections of the the combination of a rotary cutter-head, a

other cutter-head, a shaving means, and presser -means between said rotary cutter- 85 heads and said shaving means.

3. In a machine of the character described, the combination of a plurality of rotary cutter-heads comprising spaced-apart ,cuttersections, the cutter-sections of one cutterv o head operating opposite the spaces between cutter-sections of another cutter-head, shavi-ng means, and presser means between cuttersections of said respective cutter-heads and between said shaving means and sald rotary cutter-heads.

4;. In a machine of the character described, the combination of a bed, a plurality of rotary cutter-heads, a shaving knife, feeding means for causing relative feeding movement between said bed and said cntter heads and shaving knife for causin successive action on the printing plate cutter-heads and said shaving knife, presser means arranged to act on the back of the printing plate between said rotary cutterheads and between said rotary cutter-heads and said shaving knife, and means for elevating said presser means above said rotary cutter-heads.

along separated paths, presser means acting y said rotaryslide thereabove, said slide provided with a passage extending lengthwise of said cutterhead, chip directing means in said passage complemental to said cutter-head, and a standard for said slide, said standard provided with a passage for chips complement-a1 to said first-named passage.

10. In a machine of the character described, the combination of a rotary cutterhead comprising spaced-apart cutter-sections, a slide thereabove, said slide provided with openings in which said cutter-sections are received, said slide provided with a passage extending lengthwise of said cutterhead and communicating with said openings, and chip-directing means on said slide complemental to said cutter-sections and said openings.

11. In a machine of the character 'described, the combination of a plurality of provided with, cross-ribs received in asaid spaces and with openings complemental to said cutter-sections, said slide provided with cross-passages communicating with saidopenings, and chip-directing means on said slide complemental to said cutter-sections and said openings. V

12. In a machine of the character de- D scribed, the combination ofa plurality of rotary cutter-heads respectively comprising spaced-apart cutter-sections, the cutter-sections of said respective cutter-heads being opposite the spaces between cutter-sections of the adjacent cutter-head, a slide, pressermeans on said slide between proximate cutter-sections, chip-directing means on said" slide complemental to said cutter-sections, means for elevating said slide whereby to elevate said presser means through said spaces and to elevate said chip-directing meansfand means for endwise shifting of said cutterheads under said slide.

13. In a machine" of the character described, the combination of .a frame, a bed, a rotary cutter-head comprising a plurality of spaced-apart cutter-sections, a slide provided with cross-ribs received in the spaces between sald cutter-'sectlons, a 1ournal-memberfor said cutter-head journaled in said.

frame, means for releasably securing one end of said cutter-head to said journal-member,

a bearing-block for the other end of said cutwith openings in which said cutter-sections are received, a releasable hood on said slide,

said hood provided with a passage communicating with said openings, means for elevating said slide on said frame, and means for endwise removal of said cutter-head between said bed and said slide.

15. In a machine of the character described, the combination of .a frame, a support for a printing plate, cutting means complemental to said'support, and meanscausing reciprocating movement between said support and said cutting means whereby to cause cutting of said printing plate, said lastriage, fluid means causing traverse between said members, and a single operating handle controlling the speed of traverse in both directions between said members.

In testimony whereof, I have hereunto signed my name. i

LESLIE W. CLAYBOURN.

named means comprising a carriage, a cylin-' der and-a piston therein comprising a pair of actuating members, connecting means between one of said members and said carriage, and fluid means causing traverse between said members. s

16. In a machine of the character described, the combination of a frame, a support for a printing plate, cutting means complemental to said support, and means causing reciprocating movement between saidsupport and said cutting meanswhereby to cause cutting of said printing plate, said last-named means comprising a carriage, a cylinder and a piston therein comprising a pair of actuating members, connecting means between one of said members and said car- 

